This isn't necessarily from least to greatest. These are just one's I could think of off the top of my head.

1) Hearing Leonard Nimoy as Sentinel Prime for the first time. It was so surreal hearing Spock's voice coming out of a giant robot, in his likeness, no less. At same time, I was so in awe; it was like being in the presence of a god. His voice really fit the character of a seasoned Cybertronian warrior and definitely commanded respect.

2) Bumblebee crashing, throwing out Sam, transforming to bot mode and grabbing Sam in mid air, then transforming while we see Sam get put inside from his point of view!!!

3) Ironhide getting killed by Sentinel Prime. I'll admit, I had read by accident that he was going to bite the dust, but his death still left me shocked. And I was even more surprised that Sentinel was the one to do it. Also, I kind of liked Ironhide, so it made me a little sad.

4) Seeing all those people just get disintegrated by all the Decepticons firing on them was pretty shocking and disturbing to see. This movie definitely lives up to its title.

5) The entire wingsuit sequence. Man, my heart was racing the entire time because watching that whole scene in 3D made it feel like I was actually there!

6) After seeing Q get gunned down and then the Decepticon about to gun down Bumblebee, I was thinking, "No, you can't do it! You can't!" I really thought he was going to get killed off. In my opinion, out of all the things in these films, Sam and Bumblebee's relationship has always been the heart of these films. I think I was on the verge of tears.

I was shocked when Ironhide died too. I figured someone would, but I didn't think it'd be him really.

I felt sad when Bumblebee said bye to Sam. I also felt sad when the Autobots "died" by Starscream. I knew they were fine but I felt bad being in the movie's shoes you know? It was a depressing part of the movie.

__________________Whatever life holds in store for me, I'll never forget these words: "With great power, comes great responsibility." This is my gift, my curse. Who am I? I'm Spider-Man.Deviantart

It was also pretty intense and dark when Laserbeak was at that little girl's house? That wasn't expected. I can't remember what he said but it was creepyish.

He asked her when she was on the swing set, "is your daddy home?"

__________________
If I had asked people what they wanted, they would have said faster horses. - Henry Ford
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Who the **** makes a movie and while planning it is like, "you know what this needs...is some Greg Kinnear."

ALL action scenes were just, jaw-dropping and eye-popping in IMAX 3D, Bumblebee transforming mid-air, grabbing Sam and go back into car mode, just, DAMN!,The whole sequence in Chicago was just awesome.
Laserbeak was badass, it was cool to see Barricade for a couple of minutes before dying.
And Starscream vs Sam was great too "What a treat!, you and me, alone!" "I love how your little insect feet try to run!"
"After all, who would you be without me Prime?" "Time to find out..."

when Sam plants the bomb on him he says, "Eat this, Starscream!" and then Carly is like, "eat this, Starscream?!" and he responds with something like, "that's a lot pressure to think up something on the spot, Carly."

__________________
If I had asked people what they wanted, they would have said faster horses. - Henry Ford
-----------
Who the **** makes a movie and while planning it is like, "you know what this needs...is some Greg Kinnear."

2. in africa and the animals where you had a WTF moment when you hear "ALL HAIL MEGATRON" as it pans the antelopes ,then seeing latino-heat Megatron... i cant tell you i was about to freak out with a entire beast wars scream if they had done that .

There were three sequences in the movie where in my mind I was going 'this is some badass ####". When Bumblebee threw Sam, transformed, and caught Sam while reverting back to car form, everybody in the theater had to be thinking the same thing: damn. Then, when the guys were flying around the city trying to escape the decepticon air crafts; a visual moment I was very impressed with.

Third, the scene when Optimus swooped down and sliced through a horde of unsuspecting Decepticons truly conveyed the vengeance that he sought to lay down on Sentinel. I mean seriously, the last person you want to betray is the walking armory.

Just saw the movie. The only part where i really teared up was the scene when the autobots were "leaving" planet earth and the scene where bumblebee was about to be executed. There were so many cool scenes i cant explain it. Like the scene when sam was thrown out of the car and the inserted back in from his pov. That was awesome.

I had a grin on my face during the freeway scene. It was a perfect mix of great visuals and great music. I thought the movie was about to get better, but it was went back to boring human stuff for another hour before the final battle, which made the scene rather useless. Oh well, hats off to ILM for that ****ing incredible shot of Sam and Bumblebee flying through the air and transforming.

when Sam plants the bomb on him he says, "Eat this, Starscream!" and then Carly is like, "eat this, Starscream?!" and he responds with something like, "that's a lot pressure to think up something on the spot, Carly."